1. Field of the Invention
This invention relates to coupling means for joining two railroad cars and more particularly to an articulating device whereby a plurality of railroad cars may be joined to form a semi-permanent unit.
2. Description of the Prior Art
Use of standard AAR (Association of American Railroads) couplers to join railroad cars is well known. Such couplers are so designed to facilitate the connecting or disconnecting of individual railroad cars allowing the cars to be readily combined to make a train or individually separated for loading or unloading, for example.
In recent times, the railroad industry has found that the joining of several cars to form a semi-permanent unit is advantageous. For example, railroad cars particularly adapted for piggyback service have been so joined into such units and been referred to as a "10-pack." Such a unit does not need the use of the standard coupler except between units since each unit is only periodically broken to allow maintenance on an individual component. In this arrangement, therefore, one standard railroad car truck may be used to support ends of adjacent car bodies.